The present invention relates to a gear pump and a use of the gear pump.
Gear pumps mainly consist of a pair of meshing gears, which are enclosed by a housing and from which bearing journals that are arranged around the longitudinal axis project laterally away, which bearing journals are seated in plain bearings being lubricated by conveyed medium.
Since gear pumps have a pressure insensitive conveying characteristic, they are particularly suitable for the transport of conveyed media from a suction side to a pressure side. Between the latter two a pressure gradient is established due to the conveyed volume current in the downstream aggregates, which pressure gradient is particularly large for highly viscous media, and which leads to a transmission of force onto each gear. Since this transmission of force results in a load on the bearing formed by bearing journals and plain bearings, the maximum applicable pressure gradient is limited by the bearing load rating of this bearing, whereby the bearing load rating depends on the strength of the bearing journals and particularly on the diameter of the bearing journals.
A gear pump with maximum bearing load rating is known from EP-1 790 854 A1 of the same applicant. In this known gear pump the bearing journals have at least over a part of their axial extension a bearing journal diameter that lies in the range of 90% to 100% of a root circle diameter of the toothing of the associated gear.